<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8" />
  <meta name="viewport" content="width=device-width, initial-scale=1.0" />
  <title>Document</title>
  <style>
    body {
      margin: 0;
    }
    .container {
      position: relative;
      width: 100vw;
      height: 100vh;
    }

    #canvas,
    #topCanvas {
      width: 100vw;
      height: 100vh;
      position: absolute;
      top: 0;
      left: 0;
      bottom: 0;
      right: 0;
    }

    #canvas {
      z-index: 2;
    }

    #topCanvas {
      z-index: 3;
      /* visibility: hidden; */
    }
  </style>
</head>

<body>
  <div class="container">
    <canvas id="topCanvas"></canvas>
    <canvas id="canvas"></canvas>
  </div>
  <script src="./indexfix.js"></script>
</body>

</html>